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W E Stumpf

Publications and source records attributed to W E Stumpf.

At least 163 records · Page 9Linked to original sources
PubMed1982

Iodine-125-labeled triiodothyronine in rat brain: evidence for localization in discrete neural systems.

Autoradiograms prepared from adult rat brains demonstrate that nerve cells and neuropil in different brain regions selectively concentrate and retain intravenously administered triiodothyronine, by mechanisms susceptible to saturation with excess triiodothyronine. A neuroregulatory role for thyroid hormones, strongly supported by the observations, may account for their marked effects on behavior and the activity of the autonomic nervous system.

Animals↗
PubMed1982

Centrifugal innervation of the retina by luteinizing hormone releasing hormone (LHRH)-immunoreactive telencephalic neurons in teleostean fishes.

In cichlid, poecilid and centrarchid fishes luteinizing hormone releasing hormone (LHRH)-immunoreactive neurons are found in a cell group (nucleus olfactoretinalis) located at the transition between the ventral telencephalon and olfactory bulb. Processes of these neurons project to the contralateral retina, traveling along the border between the internal plexiform and internal nuclear layer, and probably terminating on amacrine or bipolar cells. Horseradish peroxidase (HRP) injected into the eye or optic nerve is transported retrogradely in the optic nerve to the contralateral nucleus olfactoretinalis where neuronal perikarya are labeled. Labeled processes leave this nucleus in a rostral direction and terminate in the olfactory bulb. The nucleus olfactoretinalis is present only in fishes, such as cichlids, poecilids and centrarchids, in which the olfactory bulbs border directly the telencephalic hemispheres. In cyprinid, silurid and notopterid fishes, in which the olfactory bulbs lie beneath the olfactory epithelium and are connected to the telencephalon via olfactory stalks, the nucleus olfactoretinalis or a comparable arrangement of LHRH-immunoreactive neurons is lacking. After retrograde transport of HRP in the optic nerve of these fishes no labeling of neurons in the telencephalon occurred. It is proposed that the nucleus olfactoretinalis anatomically and functionally interconnects and integrates parts of the olfactory and optic systems.

Animals↗
PubMed1982

The distal nephron in the chick embryo as a target tissue for 1-alpha-25-dihydroxycholecalciferol.

A histological and ultrastructural study as well as an autoradiographic analysis after injection of tritiated 1,25-dihydroxycholecalciferol (1,25-DHCC) were conducted on the distal convoluted tubules of chick embryos. Distal tubules in the embryo were shown to have the same spatial distribution as described for the adult kidney; they presented a convoluted portion located in the vicinity of the central intralobular veins and straight portions irradiating from this region towards the periphery. The epithelium in these tubules was well differentiated; its cells had numerous interdigitating folds in their lateral boundaries which were especially numerous at the basal ends. This device greatly increased the membrane surface available for interchange and was interpreted as an expression of active water and/or mineral transport. Nuclear concentration of radioactivity was found 2 h after injection of tritiated 1,25-DHCC in both the pars convoluta and the pars recta of the distal tubules. This concentration could be blocked by the previous administration of large amounts of nonradioactive 1,25-DHCC. These facts were interpreted as indicating that distal convoluted tubules in the chick embryo are functionally differentiated and contain target cells for 1,25-DHCC.

Animals↗
PubMed1981

Anatomical distribution of estrogen target neurons in turtle brain.

Autoradiographic studies with [3H]estradiol-17 beta in red-eared turtle (Pseudemys scripta elegans) show concentration and retention of radioactivity in nuclei of neurons in certain regions. Accumulations of estrogen target neurons exist in the periventricular brain with relationships to ventral extensions of the forebrain ventricles, including parolfactory, amygdaloid, septal, preoptic, hypothalamic and thalamic areas, as well as the dorsal ventricular ridge, the piriform cortex, and midbrain-pontine periaqueductal structures. The general anatomical pattern of distribution of estrogen target neurons corresponds to those observed not only in another reptile (Anolis carolinensis), but also in birds and mammals, as well as in teleosts and cyclostomes. In Pseudemys, which appears to display an intermediate degree of phylogenetic differentiation, the amygdaloid-septal-preoptic groups of estrogen target neurons constitute a continuum. In phylogenetic ascendency, e.g. in mammals, these cell populations are increasingly separated and distinct, while in phylogenetic descendency, e.g. in teleosts and cyclostomes, an amygdaloid group appears to be absent or contained within the septal-preoptic target cell population.

Amygdala↗
PubMed1981

LHRH systems in brain of platyfish.

The luteinizing hormone-releasing hormone (LHRH) system of the platyfish Xiphophorus has been studied using immunohistochemistry and retrograde transport of horseradish peroxidase (HRP). Three different populations of LHRH-positive cell bodies are present in the brain, one in the ventral telencephalon at the border to the olfactory bulb (nucleus of olfactoretinalis), one lateral to the n. preopticus (nucleus preopticus basalis lateralis) and one in the midbrain. LHRH neurons from the nucleus olfactoretinalis project via the medial olfactory tract to the olfactory bulb and to olfactory nerves. A second projection from this nucleus enters the optic tract, crosses in the optic chiasm, and courses rostrally in the outer layer of the optic nerve to the retina, where LHRH-positive nerve fibers terminate near amacrine and bipolar cells. HRP injections into the eye or into the cut optic nerve result in retrograde transport of the enzyme to the contralateral LHRH nucleus olfactoretinalis. Projections from LHRH neurons in the lateral preoptic region can be followed medially to surround the interhemispheric ventricle and laterally to border the optic tract. At the level of the postoptic commissure, LHRH fibers condense to form a fascicle which reaches the pituitary stalk to arborize throughout the hypophysis. LHRH fibers, probably in part from the midbrain LHRH neurons, project to the optic tectum, torus semicircularis, corpus and valvula of the cerebellum, as well as to the medulla oblongata. Associations of LHRH projections with sensory systems and with endocrine-autonomic systems in hypothalamus-pituitary and lower brain stem suggest a role in the modulation and integration of sensory, autonomic, behavioral and hypophyseotrophic functions.

Animals↗
PubMed1981

[Basis for a specific-active immunotherapy in malignant melanoma].

Since Morton demonstrated in 1968 that malignant melanoma is antigenic, many immunologists have taken an interest in this disease. A basis for specific active immunotherapy has been worked out at Duke University Medical Center, Durham, N.C. (USA). A female chimpanzee was hyperimmunized with melanoma cells grown in tissue culture. After appropriate absorptions the xeno-antiserum was tested by indirect immunofluorescence. Apart from unspecific activities in the serum detectable against normal human fetal and adult fibroblasts as well as other non-melanotic human tumors, following further absorptions with these cells a melanoma-specific antigen could be demonstrated on the surfaces of melanoma cells. The melanoma-specific tumor-associated antigens were further evaluated by direct and indirect immunoautoradiography. These studies suggest that there are indeed cross-reacting specific tumor-associated antigens on the cell surface of melanoma cells. At DUMC melanoma patients have therefore been hyperimmunized with melanoma cells + BCG. Clinical experience is discussed.

Adolescent↗
PubMed1981

(3-H)-dihydrotestosterone in catecholamine neurons of rat brain stem: combined localization by autoradiography and formaldehyde-induced fluorescence.

A combined formaldehyde-induced fluorescence (FIF)-autoradiography procedure was used to determine how and where the androgen, dihydrotestosterone (DHT), is associated with catecholamine systems in the rat brain. With this dual localization method, (3H)-DHT target sites can be visualized in relation to catecholamine perikarya and terminals. In the hindbrain, catecholamine neurons adjacent to the fourth ventricle (group A4), the nucleus (n.) olivaris superior (group A5), the n. parabranchialis medialis (group A7), and in the locus coeruleus (group A6) and subcoeruleal regions, as well as in the substantia grisea centralis, concentrate (3H)-DHT in their nuclei. (3H)-DHT target neurons appear to be innervated by numerous catecholamine terminals in the following hindbrain regions: n. motorius dorsalis nervi vagi, n. tractus solitarii, n. commissuralis, n. raphe pallidus, n. olivaris inferior, the ventrolateral portion of the substantia grisea centralis, n. cuneiformis, and the ventrolateral reticular formation in the caudal mesencephalon. In the forebrain, (3H)-DHT concentrates in nuclei of catecholamine neurons located in the n. arcuatus and n. periventricularis (group A12). In addition, (3H)-DHT target neurons appear to be innervated by numerous catecholamine terminals in the following forebrain regions: n. periventricularis rotundocellularis, n. paraventricularis, n. dorsomedialis, n. periventricularis, area retrochiasmatica, n. interstititalis striae terminalis (ventral portion), and n. amygdaloideus centralis. The disclosure of a morphologic association between (3H)-DHT target sites and certain brain catecholamine systems suggests a close functional interdependence between androgens and catecholamines.

Animals↗
PubMed1981

Immunohistochemical localization of enkephalin in the central nervous system and pituitary of the lizard, Anolis carolinensis.

The topographical distribution of enkephalin in the central nervous system of the lizard, Anolis carolinensis, has been studied by the immunoperoxidase technique with antiserum to leucine-enkephalin. Immunoreactive enkephalin perikarya, fibers and probably terminals are widely distributed throughout the central nervous system, which agrees well with the distribution of enkephalins in the mammalian brain. Enkephalin-containing perikarya are found in the subpallium (septum, nucleus accumbens, striatum, amydgala), preoptic and hypothalamic region, ventromedial nucleus and ventromedial area of thalamus, pretectal geniculate nucleus and posterodorsal nucleus of pretectum, nucleus of the lateral lemniscus, locus ceruleus, spinal trigeminal nucleus, nucleus of the solitary tract, medial parvocellular nucleus, and dorsal horn of the spinal cord. Enkephalinergic fibers and terminals are found in the above-mentioned areas as well as in the pallium (medial and dorsal cortex, dorsal ventricular ridge), dorsomedial and anterior dorsolateral nucleus of the thalamus, habenula, nucleus of the stria medullaris, torus semicircularis, mesencephalic tegmental area, interpeduncular nucleus, mesencephalic trigeminal nucleus, central gray, reticular formation, raphe nucleus, substantia nigra, isthmus region, and nucleus of the trapezoid body. Enkephalinergic pathways appear to exist between the septum and the medial cortex, nucleus accumbens and nucleus of the lateral olfactory tract, striatum and certain mesencephalic structures, hypothalamus and tegmentum, and between nucleus of the lateral lemniscus and torus semicircularis. In the pituitary, cells of the pars intermedia, and certain cells of the rostral pars distalis also show immunoreactivity to enkephalin antiserum. The distribution of enkephalin immunoreactivity throughout the hypothalamus and in the median eminence suggests involvement in neuroendocrine regulation. Presence of enkephalin in many extrahypothalamic brain areas indicates its important role in various sensory functions and in behavioral and autonomic integration.

Animals↗
PubMed1981

Autoradiographic studies of estrogen target cells in the forebrain of larval lamprey, Petromyzon marinus.

The distribution of estrogen target neurons is assessed in the forebrain of larval sea lamprey, Petromyzon marinus, by the use of thaw-mount autoradiography. Following the injection of [3H]estradiol-17 beta, radioactively labeled neurons are found in the ventral telencephalon and in the ventral and dorsal diencephalon, including preoptic, central hypothalamic, and thalamic regions. In the pallium no labeled cells exist. Pituitary glands, obtained from two of the animals, contain no labeled cells. The topographical distribution of estrogen target neurons in larval lamprey is similar to that of adult animals. The number of target neurons in larval lamprey, however, is lower than in the adult. The presence of target cells indicates that gonadal steroids act on the brain at this early stage of development. The lack of concentration of estrogen in pituitary cells suggests an absence of feedback regulation of estrogen at the pituitary level.

Animals↗
PubMed1981

Central noradrenergic neurones concentrate 3H-oestradiol.

Central catecholamines play an important part in the regulation of hormone secretion from the pituitary gland and in the mediation of male and female sexual behaviour. Noradrenaline has been shown to stimulate the release of luteinizing hormone (LH) probably by influencing the secretion of LH-releasing hormone (LHRH). The medial preoptic and hypothalamic areas, including the median eminence, contain noradrenaline-containing terminals which originate from discrete noradrenaline-containing cell groups in the lower brain stem. These cell groups have been identified in the pons and the medulla oblongata by histochemical methods and pharmacological experiments. Recent studies with antiserum to dopamine-beta-hydroxylase (DBH), the enzyme that converts dopamine to noradrenaline, provided evidence for the existence of noradrenergic cells. These include the locus coeruleus (group A6), a ventrally located more diffuse but continuous subcoeruleus group (group A5), a cell group located dorsal to the nucleus (n.) dorsalis motorius nervi vagi (group A2) and a cell group in or near the nucleus reticularis lateralis (group A1). Using the thaw-mount autoradiographic technique, oestradiol-concentrating neurones have been localized in many areas of the lower brain stem, including the locus coeruleus, n. tractus solitarii, n. dorsalis motorius nervi vagi, and reticular formation where catecholamine-containing neurones exist. We report here the simultaneous localization, in the same histological section, of 3H-oestradiol and the enzyme dopamine-beta-hydroxylase in neurones of the rat lower brain stem with a combined technique of thaw-mount autoradiography and immunohistochemistry, demonstrating that noradrenaline- or adrenaline-containing neurones are oestradiol target cells.

Adrenergic Fibers↗
PubMed1981

Autoradiographic studies with 3H 1,25 (OH)2 vitamin D2 and 3H 25 (OH) vitamin D3 in rat parathyroid glands.

After injection of radiolabeled 1,35 (OH)s vitamin D3, nuclear concentration of radioactivity is observed in parenchymal cells o hte parathyroid gland in pregnant, adult male, and 10-day male neonatal rats. In competition studies with unlabeled 1,25 (OH)2 vitamin D3, but not with 25 (OH) vitamin D3, in contrast to 3H 1,25 (OH)2 vitamin D3, do not show nuclear concentration in cells of te parathyroid. The results of te autoradiographic studies suggest the presence of receptors for a direct effect of 1,35 (OH)2 vitamin D3 on the parathyroid gland for modulation of parathyroid hormone secretion.

Aging↗
PubMed1981

Androgen target cells in spinal cord, spinal ganglia, and glycogen body of chick embryos. Autoradiographic localization.

After injection of 3H dihydrotestosterone, concentration and retention of radioactivity occur in nuclei of certain neurons in the spinal cord and spinal ganglia as well as in dorsal and ventral root cells of chick embryos at day 10, 12, and 18. Cell of the glycogen body show nuclear labeling at day 12, but not at day 18. In motor neurons in the midlumbar and midbrachial regions in lamina IX and in single neurons in laminae I/II, the nuclear retention of androgen is strongest, but relatively weak in ventral horn cells in thoracic and sacral segments. Neurons with nuclear labeling are also found scattered in other laminae of the dorsal and ventral horns as well as in the lateral column. When unlabeled dihydrotestosterone is administered before 3H dihydrotestosterone, nuclear uptake of radioactivity is prevented, which is not the case, when estradiol is used. The results from these autoradiographic studies indicate the presence of nuclear receptors and suggest androgen effects during prenatal stages of development.

Animals↗
PubMed1981

1,25-Dihydroxyvitamin D3 target cells in rat mammary gland.

In autoradiograms of mammary glands of rats on days 18 and 20 of pregnancy and day 6 of lactation after injection of 3H 1,25-(OH)2 vitamin D3, a nuclear concentration of radioactivity is observed in alveolar and ductal cells, as well as in cells of the epidermis of the nipple. Myoepithelial cells and connective tissue cells do not concentrate the hormone in their nuclei. The nuclear radioactivity appears specific, since 1,25-(OH)2 vitamin D3 but not 25-(OH)2 vitamin D3 prevents the uptake. The results suggest the existence of nuclear receptors for 1,25-(OH)2 vitamin D3 in mammary tissues and thus complements previous biochemical evidence showing the presence of cytoplasmic receptors for the hormone in mouse mammary glands; in addition, our results allow the identification of the cell types possessing the receptors.

Animals↗